﻿// Copyright (c) 2014 AlphaSierraPapa for the SharpDevelop Team
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
// software and associated documentation files (the "Software"), to deal in the Software
// without restriction, including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
// to whom the Software is furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.

using System;
using System.Collections.Generic;

using ICSharpCode.SharpDevelop.Dom;

namespace Hornung.ResourceToolkit.Resolver
{
	/// <summary>
	/// Determines equality of DOM members by region and fully qualified name.
	/// </summary>
	public class MemberEqualityComparer : IEqualityComparer<IMember>
	{
		public bool Equals(IMember x, IMember y)
		{
			if (x == null || y == null) {
				return false;
			}
			if (x.Region != y.Region) {
				return false;
			}
			IComparer<string> nameComparer;
			if (x.DeclaringType != null &&
			    x.DeclaringType.ProjectContent != null &&
			    x.DeclaringType.ProjectContent.Language != null) {
				nameComparer = x.DeclaringType.ProjectContent.Language.NameComparer;
			} else {
				nameComparer = StringComparer.InvariantCulture;
			}
			return nameComparer.Compare(x.FullyQualifiedName, y.FullyQualifiedName) == 0;
		}
		
		public int GetHashCode(IMember obj)
		{
			if (obj == null) {
				return 0;
			}
			return obj.Region.GetHashCode() ^
				obj.FullyQualifiedName.GetHashCode();
		}
	}
}
